Improvement in ventilating-caps for chimneys



AQBARN M. Ventilating-Gap for Chimneys, 8170.

No. 199,399. Patented Jan. 22, 1878;

WITNESSES UNITED STATES PATENT OFFICE.

ASHBELL BARNUM, or GREEN ISLAND, ASSIGNOR 0F ONE-HALF Hrs RIGHT TOGILBERT GEER, JR,

OF TROY, NEW YORK.

IMPROVEMENT IN VENTlLATlNG -CAPS FOR CHIMNEYS, 8LO.'

Specification forming part of Letters Patent No. 199,399, dated January22, 1878 application filed I January 5, 1878. V

To all whom it may concern:

Be it known that I, ASHBELL BARNUM, of Green Island, in the county ofAlbany and State of New York, have invented a new and useful ImprovedVentilating-Gap for Chimneys and Draft-Pipes, of which the following isa specification, reference being had to the accompanying drawing, inwhich- Figure 1 is aplan,Fig.2 an elevationviewed in the directionindicated by the arrows 2, Fig. 3 an elevation seen in the directionpointed by the arrows y, and Fig. 4 a vertical section in the plane 00x, all of one of my improved ventilating-caps; and Fig. 5 is a plan of adisk of sheet metal, from which all the hooded portion of the cap can beformed in one piece.

This invention consists in the combination, with the tubular part A, ofa cap composed of the pairs of opposite-inclined hoods B B G O, ofapproximately semi-conical form, and arranged radially in a circlearound a common center, and connected together and closed at their topsby the plate or part 01, and united along their inturned side parts e,and all shaped, proportioned, and arranged together, and in respect tothe said tubular part, substantially as shown in the aforesaid drawings,and hereinafter described, the ornamental piece w being not essential tothe invention.

The whole cap, composed as above specified, can be molded or cast in onepiece of cast-iron or other suitable metal or plasticmaterial and it canbe made of suitable pieces of metal or other material, properly unitedtogether. I however commonly prefer to construct the cap from onecircular piece, V, Fig. 5, of metal, by bending or swaging the same intothe proper shape, (shown in the other figures,) and slitting the outerend parts of the inwardly-turned portions 0, or of the parts to beturned inward, as indicated at a in Fig. 5, and bending the samedownward, so as to form lugs f, which are to be riveted or otherwisefastened to the tube A of the chimney or draft-pipe, substantially asindicated in the drawing.

In that caseI commonly prefer to have the diameter of the disk V abouttwice and one-half the diameter of the tube A with which the cap is tobe combined and I gen erally prefer to have the length of the upper side9 h of the inclined part of each semi-conical hood about equal to thediameter of that tube, and to have the top parts 9 h and inturned partse of the pairs of hoods inclined at such angles in respect to eachother, and arranged and secured upon the top of the tube A in suchposition, that the outer ends of all the hoods shall project equally inradial directions beyond the circumference of that tube, and that thehighest end parts h shall be about 011 a level with, or somewhat abovethe level of, the top of the tube A, while the lowest partsi of theouter ends of thehoods shall be considerably below and outside of thetop of the tube, all substantially as shown in the drawing.

The improved ventilating-cap above described is, even when formed ofthin sheet metal, very stiff, strong, and durable,to resist the force ofwind and rain, and will effectually prevent rain and sleet from fallingor beating into the draft-tube.

The blowing of the wind downward, either vertically or in any inclineddirection, upon the cap produces a partial vacuum under the overreachingouter end parts of the hoods B B O O, as at t, and thereby causes astrong upward draft through the pipe A, and thence outward under thehoods, as indicated by the arrows, s, Fig. 4:.

The blowing of the wind horizontally against the cap in the lengthwisedirection of either one of the pairs of opposite hoods, as B B, andacross the other pair, 0 O, as indicated by the arrows y in Fig. 1, willalso produce a very strong upward draft through the tube A but theblowing of the wind horizontally against the cap in a direction parallelwith the plane 0' r, Fig. 1, of either one of the two pairs of oppositeinturned parts 6 between the hoods, as indicated by the arrows 2, willproduce only a moderate upward draft through that tube.

This improved ventilating-cap is, therefore, suitable for use onchimneys and draft-pipes which are liable, by reason of some adjacentbuilding or structure, to have the natural upward draft therein impededor overcome by winds blowing downward or in some particular horizontaldirection; and it is especially adapted for use on the exit-pipes of thestoves and ventilators of railway-cars.

In applying this improved ventilating-cap to the exit-pipe of a stove orventilator of a railway-car, the draft therein can be rendered very muchgreater while the car is running than when it is at rest by simplyarranging and securing the cap on the exit-pipe with the plane 00 m ofone pair of the opposite hoods, as B B, in the lengthwise or runningdirection of the car, while the plane of the other pair of hoods, as OG, is at right angles to that direction.

In case it'shall be required that the draft in the exit-pipe of the carshall not be very materially greater while the car is running than whileit is at rest, this ventilating-cap, to secure that result, is to bearranged and fastened on the exit-pipe with the plane r r of one of thepairs of opposite inturned parts e e in the direction of the length andmovement of the In testimony whereof I hereunto set my hand i in thepresence of two subscribing witnesses this 26. day of January, 1878.

' ASHBELL BARNUM.

Witnesses:

AUstrnvF. PARK, J AMIES T. GooDFE Low.

